X4 Pharmaceuticals (XFOR) investor relations material

Program updates and trial design

• Lead program mavorixafor is in phase III (4WARD trial) for chronic neutropenia, targeting increased neutrophil counts and reduced infections.

• Enrollment target was reduced to 126 patients after FDA agreement, aiming for completion by year-end.

• Powering for infection and ANC endpoints remains strong at 88% and 93%, respectively, with conservative assumptions maintained.

• Operational improvements, including a CRO change, have accelerated enrollment and increased U.S. patient participation.

• The trial enrolls a sick population with low ANC and frequent infections, aligning with FDA guidance.

Safety, efficacy, and future studies

• Over 500 patients have received mavorixafor, and the FDA considers the safety database sufficient for review.

• The trial is designed for a one-third reduction in infection rate, which is seen as commercially meaningful.

• No stratification by disease subtype; about 50% of patients are idiopathic, and G-CSF use is randomized but not capped.

• Dose selection is based on robust pharmacokinetic and phase II data, supporting efficacy and safety.

• A new open-label G-CSF titration study is planned to guide reduction or discontinuation of G-CSF in patients.

Market opportunity and commercialization

• Estimated 15,000 U.S. patients with chronic neutropenia and recurrent infections, mostly managed in community hematology practices.

• Patients are accessible through hematologists, and the market is expected to shift with the introduction of an oral alternative to G-CSF.

• Pricing is anticipated in the $200,000–$300,000 range annually, below the WHIM indication price.

• No advanced competitors beyond G-CSF are currently identified.

• U.S. commercialization will be direct, with a sales force of 50–60 reps and 5–6 regional managers; ex-U.S. options depend on partner decisions.